Location: Food and Feed Safety ResearchTitle: Escherichia coli O157:H7 populations in ruminants can be reduced by orange peel product feeding Author
|Carroll, Jeffery - Jeff Carroll|
|Nisbet, David - Dave|
Submitted to: Journal of Food Protection
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/7/2011
Publication Date: 11/9/2011
Publication URL: http://handle.nal.usda.gov/10113/57239
Citation: Callaway, T.R., Carroll, J.A., Arthington, J.D., Edrington, T.S., Rossman, M.L., Carr, M.A., Krueger, N.A., Ricke, S.C., Crandall, P., Nisbet, D.J. 2011. Escherichia coli O157:H7 populations in ruminants can be reduced by orange peel product feeding. Journal of Food Protection. 74:1917-1921. Interpretive Summary: E. coli O157:H7 can live in the intestinal tract of food animals, where it poses a threat to human consumers of meat products. Orange peels are a by-product of juice production that represents a significant waste stream and have been fed to cattle as a least-cost ration ingredient for many years. Citrus peels contain essential oils that act as antimicrobials against bacteria. This study was designed to investigate if the feeding of citrus peel and pulp affected populations of E. coli O157:H7 in experimentally infected sheep. Results indicate that feeding orange peel at levels of 5% and 10% decreased E. coli O157:H7 populations in the cecum and rectum of sheep. Our results demonstrate that orange peel and pellets are environmentally friendly, low-cost products that can be used as a pre-harvest intervention as part of an integrated pathogen reduction scheme.
Technical Abstract: Foodborne pathogenic bacteria such as E. coli O157:H7 are threats to the safety of beef and are publically perceived as “hamburger diseases.” Fresh citrus peel and dried orange pulp are by-products from citrus juice production that have a relatively high nutritive value (high TDN). Orange peel and pulp is available at low prices in citrus-producing regions and is thus often incorporated into least-cost ration formulations for beef and dairy cattle. Because of the natural antimicrobial effects of orange peel/pulp, it has been proposed for use as a low-cost feed ingredient that could be used to decrease foodborne pathogenic bacteria populations in cattle. We have previously reported that orange peel and pulp reduced (P < 0.05) populations of E. coli O157:H7 and Salmonella in mixed ruminal fluid fermentations in the laboratory and reduced growth rate (P < 0.05) and final populations (P < 0.05) of pathogens in pure culture studies. Therefore, this study was designed to determine if the antipathogenic effects of orange peel and pulp were effective against E. coli O157:H7 in vivo. Sheep (n = 24) were fed a cracked corn grain-based diet that was supplemented with a 50%/50% mixture of dried orange pellet and fresh orange peel to achieve a final concentration (DM basis, w/w) of 0%, 5%, or 10% pelleted orange peel for 7 d. Following this adaptation period, sheep were artificially inoculated with 1010 CFU E. coli O157:H7 by oral dosing. Fecal shedding of E. coli O157:H7 was measured daily for 5 d before animals were humanely sacrificed, and it was reduced (P < 0.05) in sheep fed 10% OP after 96 hrs post-inoculation. Populations of inoculated E. coli O157:H7 were reduced by OP treatment throughout the gastrointestinal tract; however, this reduction reached significant levels in the rumen (P < 0.05) of sheep fed 10% OP diets. Cecal and rectal populations of E. coli O157:H7 were reduced (P < 0.05) by inclusion of both 5% and 10% OP diets. Our results demonstrate that orange peel products are environmentally friendly and low-cost products that can be used as a pre-harvest intervention as part of an integrated pathogen reduction scheme.